As this, the LT1 tester and document are included with all Digitrax command stations and used mainly (as per instructions) for testing purposes, I think they suggest it is applicable to all Digitrax command stations as a voltage limiting test track off rail A and rail B. No were is it stated as limited to the DB150

As per Digitrax :

How do I test a mobile decoder?

The LT1 is a simple decoder tester.

LT1 Instructions (.pdf)

The LT1 is included with all Digitrax Starter Sets. It consists of a harness with 6 conductor Telco type wire and a male plug, a tester with a female 6 conductor jack and a protection resistor.

We get so confident that we drop this and just test it on the program track. If it reads back, no reason to test it on a test track. The engine MUST allways acknowledge the command station via pulse to motor on the programming track. If it shorts out or anything, you will know.

I found my resistor from my LT1 tester. I had shrink-wrapped the resitor but forgot to identify it. Now I remember.

My test track was taken from an MR article. It has a few pieces of track, a single turnout controlled by a ground throw, a rerailer. I use a center-off DPDT toggle to switch between programming and run on a Zephyr. I have never had a need for a resistor.

But Digitrax does say a 1K resistor could be required between PROG A and PROG B in some cases, Bachmann is an example. Not my case.